Abstract: Objective To compare the proteomics discrepancies between osteosarcomas and normal tissue of bone for discovering specific markers for osteosarcoma. Methods Total protein was extracted from five samples of osteosarcoma and five samples of normal bone,respectively.Then dielectrophoresis was conducted three times,repeatedly.The differential proteins were found out by ImageMaster 2-DE software analysis after silver staining and scanning.Then, MALDI-TOF/TOF mass spectrometric identification of differential protein spots was conducted.Get access to the peptide mass fingerprints and query to find out matching proteins in the NCBI database. Results Dielectrophoresis silver staining map had good repeatability.Protein spots of osteosarcomas and normal bone were approximately(1 296±179),(1 108±162),respectively,and 25 significant different proteins were discovered,of which 10 spots were identified successfully.Six proteins were significantly up-regulated in osteosarcom,especially the level of glutathiones transferases（GST）.Four down - regulated proteins were observed，especially the level of nucleoside diphosphate kinase（NDPK）. Conclusion The different proteins between osteosarcoma and normal tissue can be found by proteomics analysis which provide the basis for searching the specific marker for osteosarcoma.